Device for controlling the upper threads on sewing-machines.



J. R. MOFFATTI DEVICE FOR CONTROLLING THE UPPER THREADS 0N SEWING MACHINES.

APPLICATION FILED MAY 11, 19H. I

1,139 793o I Patented MaylS, 1915.

2 SHEETSSHEET 1. l\

lV/YNESSES A llorneyg J. R. MOFFATL DEVICE FOR CONTROLLING THE'UPPER THREADS 0N SEWING MACHINES.

'APPLICATION FILED MAYH, 1911.

1,19 793. Patented May 18,1915.

'2 SHEETS-SHEET 2- snares area a JAMES R. MOZEFATT, OF CHICAGO, ILLINOIS, ASSIGNOR '10 UNION SPECIAL MACHINE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

DEVICE Iron. con'rnonmne THE UrPEa THREADS on SEWING-MACHINES.

Specification of Letters Patent.

Patented May 18,1915.

Application filed May 11, 1911. Serial No. 623,511.

To all whom it may concern:

Be it known that 1, JAMES R. MOFFATT, a citizen of the United States, residing at Chicago, in the county of Cook, State of Illinois, have invented certain new and useful Improvements in Devices for Controlof D. 'W. Corey, filed May 21st, 1901, Serial No. 61,291, that is, to prevent the needles from carrying down too much thread; and to hold the thread reasonably taut when the needles begin to move up, but release it in time for the feed dog to move the fabric forward. I

So far as the particular construction of the clamping or nipping device is concerned, it is applicable to either single or double chain or look stitch machines, and to single or multiple needle machines.

I have especially designed this improvement, however, for use on multiple needle machines, each needle thread passing through a separate pair of nipping jaws,

thus avoiding the frictional contact or rolling over of one thread upon another; and by operating all the nipping jaws at the same time and by the same device, I am enabled to get a uniform tension or grip on all the threads.

The invention, therefore, consists primarily in the application to a multiple needle sewing machine, of separate nipping devices for each thread, all operated from a common device and with uniform tension; and secondarily it consists in the details of construction of the thread-nipping devices and other operating means. 1

The invention is illustrated-in the accompanying. drawings, in which,

Figure 1 is a side elevation of a multiple needle sewing machine embodying my in vention; Fig. 2 is a top plan View; Fig. 3 is a detail. elevation partly in section, illustrating the thread-nipping and operating devices in the unclamped position of the former; Fig. 4 is a detail view of the same in clamped position; and Fig. 5 is a detail of the operating means.

In these drawings, 1 represents a sewing machine of the well known Union Special multiple needle type having the plurality of needles 2, the needle lever 3, the needle bar eyelet 4, the needle lever eyelet 5, the adjustable stationary eyelet 6, on the gooseneck and the usual tensions 7. The loopers cooperating with the needles are not shown,

but in this particular type of machine are 0f the non thread-carrying type, the machine making a plurality of-rows of single chain stitches. Upon the top of the gooseneck is secured the yoke 8, the arms of which support a sliding rod 9, upon which is loosely supported a series of thread-clamping diskslO, a pair for each thread. This rod has on one end a headed shank 11, and between the head and the arm 12 of the yoke 8 surrounding the shank is a spring 13. Upon the other end of the rod 9 beyond the arm 14 of the yoke, is secured a nut 15.

When the rod 9 is drawn toward the front of the machine, the inner end of the shank 11 sliding through the arm 12 engages the inner one of the clamping disks, and through the washers 24: on the rod crowds all the disks together with uniform pressure against the tension of the spring 13, and thus causes each pair to grip its particular thread; the threads being guided to and from the respective pairs of disks by the eyeleted plates 16.v When the force tending to draw the rod 9 forward relaxes, the spring 13 returns the. same to normal position.

As a means for alternately clamping and releasing the threads, that is, for clamping the disks and permitting the rod 9 to return to normal position under the action of the spring 13, thus Withdrawing the inner end of the shank 11 from contact withits adjacent disk, I have provided the lever 17 pivoted in the bracket 18 on the front of the gooseneck, and having an upwardly extend- I dle lever rides up and down the inclined projection, thus swinging the lever 17 and" causing the shank 11 to engage its adjacent disk, thus transmitting a uniform gripping action to all the disks.

When the needle bar is at the upper end of its stroke, the clamps are free from'the thread, so that during the first part of the downward movement of the needle, and while the final forward feeding movement is taking place, the thread is free. As soon as the eye of the needle approaches the work support, the clamping action begins, so that as soon as the point is into the previous needle loop and the needle loop is shed from the looper, the needle thread will be clamped and the farther downward movement of the needle will draw up the previously shed needle loop. As this clamping action is at its height when the needles start up, 1t prevents the feeding of fresh thread from the spools when the needles start to move up ward, and as it lasts during a considerable portion of the upward movement, it aids in drawing up the stitch by keeping the thread taut, but releases the thread in time for the feed dog to move the fabric forward, and to allow thread to be pulled from the supply.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is

1. A sewing machine comprising stitchforming mechanism including a plurality of reciprocating needles, means for drawing thread from the supply, a plurality of clamping devices for the needle threads, and means operating simultaneously on all of saidclamping devices at each reciprocation of the needle for causing the clamping devices to alternately clamp and release the threads,

7 said means including a sliding rod upon which the clamping devices are supported.

2. A sewing machine comprising stitchforming mechanism including a plurality of needles, a needle lever for reciprocating the same, means for drawing thread from the I supply, clamping devices for the needle threads located between the supply and the means for drawing oif the thread, means operated by the movement of the needle lever for operating simultaneously all said clamping devices to causethem to clamp the thread, and a spring for keeping the clamping devices normally open, said means ineluding a sliding rod upon which the clamping disks are supported with washers on said sliding rod between the respective pairs rod upon which the clamping devices are supported, a spring controlling said rod andkeeping it normally in one position, and means for sliding the rod against the pressure of the spring, said rod having a shoulder adapted in its movement to engage the adjacent clamping device and transmit uni form clamping action to the clamping devices.

4. A sewing machine comprising stitchforming mechanism including a needle lever and a plurality of needles, means for draw 1 ing thread from the supply, a clamping device for each needle thread located between the supply and the means for drawing. oi the thread, means operated by the movement of the needle lever for operating simultanee ously all said clamping devices to cause them to clamp the thread, and a spring for keeping the clamping devices normally open, said means including a member on the needle lever and a pivoted lever engaged by said member and operatively engaging the clamping device support.

5. A sewing machine comprising stitchforming mechanism including a plurality of needles, and means for drawing thread from the supply, a clamping device for each needle thread located between the supply and the means for drawing o3 the thread, a sliding rod upon which the clamping devices are supported, and means for sliding the rod in one direction at each reciprocation of the needles, including a pivoted lever adapted to be brought by the action of a moving part of the machine into engagement with the rod to positively slide it in one direction.

6. A sewing machine comprising stitchforming mechanism including a plurality of needles, and means for drawing thread from the supply, a clamping device for each needle comprisinga yoke, a rod sliding in the arms of said yoke, thread-clamping devices upon said rod between the arms of said yoke, a shoulder on said rod adapted in its movement to engage and close the clamping devices, a spring for keeping the rod normally retracted, and a pivoted lever for operating the rod in one direction, and means for operating said lever.

8. In a sewing machine, a needle, a tension device, a plurality of tension disks,=a holder for said tension disks, means for intermittently clamping said tension disks, said means for intermittently clamping said disks being operative to clamp the threads at a period of time just before the needle reaches its lowest point and also before it reaches its highest point.

9. A sewing machine comprising stitch forming mechanism including a plurality of reciprocating needles, means for drawing thread from thesupply, and a tension device for the needle threads comprising a plurality of tension disks located between the needles and the means for drawing the thread from the supply, a frame, a support for the tension disk slidingly mounted upon said frame, and means for sliding said support including a lever pivoted between its ends, one end of saidlever coacting with said support and having a cam on its other end adapted to engage a moving part of the machine which oscillates the lever for each reciprocation of the needles.

10. In a sewing machine, a needle lever and means to vibrate it, a tension device including a plurality of disks, a support for said disks, a pivoted lever, said pivoted lever having one end in engagement with said needle lever to impart a movement to said ivoted lever in a horizontal plane whereby the support for said disks can be reciprocated to impart a clamping action to said disks.

11. A sewing machine including in combination a needle, a needle lever for reciprocating the same, means for drawing the needle thread from the supply, a tension device for engaging the needle thread between the thread drawing means and the needle, and a lever forintermittently releasing the tension device, said lever being pivoted between its ends at a point in a horizontal plane above the needle lever, and having means engaged by the needle lever whereby said lever is oscillated.

In testimony whereof I aflix my signature,

in presence of two witnesses.

JAMES R. MOFFATT. Witnesses:

C. MGNEIL, A. B. CLOTHIER. 

